Avalanche Forecast

Issued: Nov 11th, 2020 8:00AM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Storm Slabs and Wind Slabs.

percy woods,

Steep solar aspects in the alpine may harbourĀ  pockets of windslab on a sun crust. Watch for thin storm slabs at and above treeline.

Summary

Weather Forecast

Cloudy with sunny periods and isolated flurries. -12C for an alpine high along with light westerly winds and a freezing level of 600m. Similar weather for Thursday with a trace of precipitation. Friday brings scattered flurries and freezing level rising to 1100m.

Snowpack Summary

7cm of storm slab sits on top of the previous dust on crust surface. The thin soft storm slab was easy to trigger at treeline on steeper terrain. Last week rain fell as high as 2500m, with 50cm of snow accompanied by extreme W winds at upper elevations. The weekend saw strong N'ly winds, causing reverse loading of storm snow into S'ly lees.

Avalanche Summary

One size 1 skier controlled storm slab 7cm deep, 25m wide ran 300m on a steep NE aspect at 2100m in the west end of the park. A recent size 1 Sa occurred on a steep S aspect on Mt Rogers where recently formed windslab triggered on top of the Nov 5th crust. Watch for frozen debris from the previous wet avalanche cycle.

Confidence

Due to the number and quality of field observations

Problems

Storm Slabs

An icon showing Storm Slabs

Watch for thin soft storm slabs at and above treeline. These slabs may be of consequence in steep confined terrain features such as gulleys where they could gain greater volume.

  • The new snow will require several days to settle and stabilize.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 1.5

Wind Slabs

An icon showing Wind Slabs

Reverse loading from outlfow winds has built small pockets of windslab in immediate lees. These sit on a firm crust below 2500m and higher on steep solar aspects.

  • Keep an eye out for reverse loading created by outflow winds.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Nov 12th, 2020 8:00AM